Heat-sealable, moistureproof coating compositions and coated packaging material incorporating same



United States Patent 3 403,048 HEAT-SEALABLE, MbISTUREPROOF COATINGCOMPOSITIONS AND COATED PACKAGING MATERIAL INCORPORATIN G SAME James H.Grimm, Milford, N.J., and Francis J. Wieloch, 5

Penfield, N.Y., assignors to Riegel Paper Corporation, New York, N.Y., acorporation of Delaware No Drawing. Continuation-in-part of applicationSer. No, 336,885, Jan. 10, 1964. This application May 3, 1967, Ser. No.635,667

6 Claims. (Cl. 260-3) ABSTRACT THE DISCLOSURE Cross reference to relatedapplications.-This application is a continuation-in-part of copcndingapplication Serial No. 336,885, filed January 10, 1964, forHeatSealable, Moistureproof Coating Compositions and Coated PackagingMaterial Incorporating Same, now abandoned.

Summary of the invention.-In the packaging of food products, forexample, it is often important for the wrapping or packaging material tohave predetermined barrier properties, as regards the transmission ofwater vapor and gas, either into or out of the package. In addition, thepackaging material desirably should be suitable for formation andclosure by heat-sealing techniques, under circumstances which willprovide for a high-strength seal under a fairly wide range of operatingconditions, such as may be experienced in regular production operationson various form and fill packaging machines. These and additionalcharacteristics desirable and acceptable in a commercial packagingmaterial are imparted to packaging substrates by the new and improvedcompositions of the invention. Among other beneficial characteristics ofthe new coating are good gloss, adequate scufr' resistance, sufficientflexibility, resistance to blocking, ability to accept pigments,clarity, ability to form stable solutions, etc. Various coated packagingmaterials now available for practical commercial use, while having someof the desirable characteristics sought in an ideal packaging material,are substantially inadequate in other respects. Particularly, it hasbeen difficult to achieve desired moisturcproof and heat-seal propertiesin a form and fill packaging material of acceptable cost withoutintroducing ingredients which would be undesirable for food packaginguse.

As an important aspect of the invention, the new coating compositionincorporates, as a principal film-forming constituent, relatively highlysaturated cyclicized rubber, advantageously a cyclicized natural rubberhaving an iodine value of approximately 95 or less. The highly saturatedcyclicized rubber, which most advantageously constitutes about 50percent of the new composition, is modified by the addition of wax, forimproved water vapor transmission rate (WVTR) properties, and by theaddition of a vinyl or similar modifier for improved heat-sealcharacteristics. In one particularly advantageous composition, the waxmodifier constitutes about percent 3,403,048 Patented Sept. 24,4968

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of the composition and the heat-seal modifier constitutes about 30percent of the composition, although tliese percentages will, of course,vary somewhat with the characteristics of the specific modifiers.(References herein to percentages or parts of constituents meanspercentage or 'parts by weight, unless otherwise specified.)

A glassine substrate coated with the composition of the inventionexhibits markedly superior WVTR and gas barrier charasteristics, whileat the same time providing fiber tear heat seals at extremely lowcoating weights. These primary characteristics, coupled with additionaldesirable properties, make the composition particularly suitable andadvantageous for use in conjunction with the package of foods.

More specifically, the present invention provides, in a single surfacecoating, both adequate fhot tack and adequate non-sticking propertiesfor sheet materials especially adapted for use in the rapidly developingfield of form and fill packaging. As is known in the art, a form andfill machine is a high speed, automatic, bag former and filler whichgenerally operates by overfolding a continuous web and continuouslyforming a longitudinally extending seam to define a continuous tube.Thereafter, the tube is transversely sealed, filled through the openend, advanced, and then sealed transversely. Each transverse seam forms,in elfect, the top of one package (a filled package) and the bottom ofthe next package to be filled.

In order to be operated at economically feasible, very high speeds, thesealing jaws of the packaging machinery must remain uncontaminated fromthe coatings of the packaging material and must be able to effect,without an unnecessarily long dwell, a seal having suflicient hot tack.It should be understood that a freshly formed bag seam with sufficienthot tack will remain cohesive and intact under the stress of thepackaged contents while the adhesive is setting (tacky) and after thesealing jaws have been withdrawn.

In previously known coating compositions, acceptable hot tack propertieshave been obtained at the expense of the non-stick properties and viceversa. That is to say, the coatings of the prior art possess eithersufiicient hot tack or suificient non-stick properties but nonepossesses a high degree of both, as is most desirable for use in veryhigh speed form and fill equipment.

Specifically, it has been discovered that an ethylenevinyl acetatecopolymer is an especially efiective heat seal modifier for use with ahighly saturated cyclicized rubber and a high melting point wax toprovide a new and improved coating composition having unexpectedlysuperior form and fill properties, i.e., high hot tack and highresistance to sticking and having superior resistance to water vaportransmission. Moreover, it has also been determined that theseextraordinary coating compositions, simultaneously having highlydesirable anti-sticking and hot tack properties, as well as an extremelylow WVTR, may be readily formed into solvent solutions and coated uponprinted substrates to form clear, transparent barriers having goodgloss.

The particular cyclicized rubber compound employed to great advantage inthe practice of the invention has a very high melting point (at least125 C.) and a low iodine value (-95) in comparison with the conventionalPliolitc type cyclicized rubbers employed heretofore in packagingcoating compositions of the prior art. More specifically, cyclicizedrubbers for the practice of the invention may be prepared by carrying areaction between an inorganic acid and a rubber to substantialcompletion to yield a substantially completely saturated conversionproduct. In significant contrast, the Pliolitc type of cyclicizedrubbers are comparatively less than substantially completely saturated,and are usually prepared by a. controlled process which-results in asubstantially ingop plete reagtionof therubber and acid. Thenon-equivalence of the two types of cyclicized rubbers is clearlyevidenced by significant differences in melting points and iodinevalues.

In a most advantageous specific embodiment of the invention, the mainconstituent of the composition is a cyclicized natural rubber, as madeavailable as of January 10, 1964, the filing date of the aforementionedcopending application Ser. No. 336,885, under the trade designation RCI92-154, by its manufacturer, Reichhold Chemicals, Inc. RCI 92-154 is ahard, tough, hornlike, resinous polymer which is prepared by carrying tosubstantial completion the reaction between. rubber and an inorganicacid in the presence of a phenol catalyst, and which has the followingapproximate properties and characteristics as specified by themanufacturer, Reichhold Chemicals, Inc.:

Specific gravity: 25 C. 1.00 Wt. per gal.-25 C 8.33 Bulking value25 C.0.120 Index of refraction-25 C. 1.535 Color, U.S.D.A., Rosin scale MMelting point, B & R method, "C 145-165 Melting point, capillary method,C 125-135 Molecular weight, average 5,000-10,000 Iodine value 75-95 Acidvalue -1 Saponification value 0 Burning rate Very slow Dielectricconstant, 1000 cy. 1.35-1.50 Specific surface resistance, ohm Hardness,Sward 50-60 The specific portion of RCI 92-154 in the new and improvedcoating composition can be varied, as will be understood, however, thebest WVTR characteristics are realized when the percentage of RCI 92-154is above about percent and less than about 70 percent, and the verybest, indeed optimum, results are realized when the percentage of RCI92-154 is approximately percent (i.e., above 40 percent and less thanpercent).

It has been determined that the more unsaturated types of cyclicizedrubbers (e.g., Pliolite resin P-1230) are unsatisfactory in the newcompositions and are clearly nonequivalent resins for the purposes ofpracticing the in vention described in this application. Specifically,experiments using Pliolite resins (which have high iodine values),certain phenol reacted products, other resins including phenolicmodified rosin (e.g., maleic anhydride modified rosin), and the like assubstitutes for the RCI type resin in the new compositions failed toprovide coating compositions having comparable properties to those ofthe coating compositions in which the RCI 92-154 cyclicized rubber wasemployed. For example, the new compositions employing RCI 92-154 resinmay be readily dissolved in toluene or a similar solvent to establish astable, working solution which may be applied to substrates byconventional techniques and which will dry to form a clear coating.However, when a more unsaturated rubber (e.g., a Pliolite P-1230 resin)is substituted for the specified highly saturated rubber (RCI 92-154),it is impossible to form a stable, working solution (i.e., one whichwill completely dissolve as a clear, non-separating solution and whichwill dry as a clear coating) in toluene or any other solvents.

To illustrate further the critical importance of the RCI 92-154 typeresin in the new composition, formulations substituting another wellknown film-forming constituent (maleic anhydride modified rosin,available from Reichhold Chemical Co. as Beckacite 1110) for the RCI 92-154 resin were prepared and tested for hot tack. The new coatingcompositions and the compositions containing the Beckacite 1110 wereidentical, but for the substitution of Beckacite 1110 resin for the RCI92-154 resin. The results of these tests proved that other resins (suchas a maleic anhydride modified rosin) when em ployed ,in lieu of thespecified highly saturated cyclizecl rubber do not provide comparablecompositions in terms of hot tack, etc.

Through the aforementioned experimentation, including testing andevaluating heat seal coating compositions which included variouscyclicized rubber resins prepared from both natural and syntheticrubbers, it has been discovered that only resins, of which the resin RCI92-154, manufactured by Reichhold Chemicals, Inc. is representative, areeffective in providing a composition having the requisite properties ofhot tack, anti-stick, low water vapor transmission, etc., when combinedwith modifiers such as ethylene-vinyl acetate copolymers and parafiinwax.

As mentioned hereinabove, one of the significant modifiers utilized inthe composition of the invention is wax, and in a specifically preferredcomposition, the wax employed is parafiin having a melting point of136-140 F. and sold by the Sun Oil Company under the designation Sun4312 Paraffin Wax. Microcrystalline and vegetable waxes can be used withacceptable results, although parafiin wax is much preferred for thebetter WVTR characteristics it imparts to the composition. Waxes oflower melting point than the specified range, While providing animprovement in WVTR characteristics, tend to lessen the resistance ofthe composition to blocking. Higher melting point ranges, on the otherhand, while improving resistance to blocking, tend to reduce WVTR properties, particularly as measured on coated substrates in a creasedcondition. Thus, while the particular Wax may be chosen in accordancewith specific end use requirements, the specified wax provides anoptimum balance for general use.

A second significant modifier utilized in the new compositions is aconstituent imparting heat scalability. The most advantageous group ofheat-sealing modifiers are vinyls and vinyl copolymers, although certainother compatible heat-sealable compositions have been employed. Perhapsthe most advantageous specific heat sealing modifier is a vinylacetate-ethylene copolymer manufactured by E. l. du Pont de Nemours &Co., Inc., under the trade designation Elvax 250. Based uponexperimental results, it appears that the heat-sealing modifier may beemployed in the new composition in amounts ranging from about 3 percentto about 65 percent, although it appears that optimum results areachieved using about 30 percent.

In addition to the beforementioned major components of the newcompositions, it is desirable in certain instances to utilize minorquantities of additional additives such as anti-oxidants, ultravioletabsorbers, pigments, gloss controllers, mold release agents, and thelike. The basic composition appears to be compatible with a Wide rangeof such minor additives. Suitable anti-oxidants are compositions ofbutylated hydroxy toluene or butylated hydroxy anisol. A small quantity(e.g., 1-3 percent) usually is adequate. For non-food uses, anultraviolet absorber, such as Uvinol 400, a substituted benzophenone,may be used instead of or in conjunction with an anti-oxidant.

The composition of the invention may be readily dissolved in and is mostreadily applied to a substrate from an aromatic solvent solution.Typically, the substrate is coated upon one or both surfaces with thesolvent being evaporated to form a continuous, clear, glossy and solidfilm. The common aromatic hydrocarbons (for example, benzene or toluene)have been found to be suitable solvents, and naphtha may also beutilized Where expedient. Typically, the solvent solution comprises onthe order of to percent of the solvent and 30 to 20 percent of the newcomposition.

In a typical application, a glassine substrate web of about 30 poundsbasis weight is coated on each side with about 1.5 to about 3 pounds perream (3,000 square feet).

v 1 A coated substrate is considered to have good blOllklIlg resistancewhen two sheets, held together under psi. at F. for 24 hours, show notendency to tick 01' mar upon separation.

However. where WVTR requirements are of "relatively less significance,lower coat weights can be utilized. Fiber tear heat seals are possibleusing coat weights as low as 0.6 pound per ream, although a morepractical lower limit for commercial operations is about 1.5 pounds perream. I

i In addition to the heat-seal modifiers referred to above, it has beendetermined that the following commercially available compositions (inaddition to other vinyls, acrylics, styrenes, and their copolymers, aswell as other rosin 5 esters and other wood-derived resins) willapparently form useful heat-seal modifiers: Polyisobutyl methacrylate,manufactured by E. I. du Pont de Nemours & Co., Inc., under the tradedesignation Lucite 45; acrylateethylene copolymers, manufactured byUnion Carbide Co., under the trade designation Bakelite DQ DA2100 andBakelite DQ DA3270; vinyl acetate-vinyl chloride copolymers (13% vinylacetate), manufactured by Union Carbide Co., under the trade designationVYHH; vinyl acetate-ethylene copolymers (18% vinyl acetate), manu-*factured by E. I. du Pont de Nemours & Co., Inc., under TABLE II RCIElvax 250 Sun 4312 Coating 92-154 (phr.) paraffin Heat-seal 2 WVTR 1weight wax (1 100 63.6 0 Outstanding 6.22 2.95

" Per hundred parts rubber. For footnotes 1 and 2 see Table I.

TABLE I' Formulation:

RCI 92-154, 46%. Sun 4312 parafiin wax (melting point 140 F.).Heat-sealing modifier (as identified below), 29%.

Heat-seal characteristics 1 Good.

Heatsealing modifier WVTR 1 XYHL Polyvinyl Butyral, manufactured byUnion Carbide Co. AYAF Polyvinyl Acetate (softening point 77 0.),manufactured by Union Carbide Co.

AYAT Polyvinyl Acetate (softening point 87.5 C.), manufactured by UnionCarbide Co.

Elvax 250 Vinyl Acetate-Ethylene Copolymer (28% vinyl acetate),manufactured by E. I. du Pont de Nemours & Co., Inc.

Elvax 150 Vinyl Acetate-Ethylene Copolymer (33% vinyl acetate),manufactured by E. I. du Pont de Nemours & Co., Inc.

Elvax 3602 Vinyl Acetate-Ethylene Copolymer vinyl acetate), manufacturedby E. I. du Pont de Nemours & Co., Inc.

Vinylite VMCH Vinyl Acetate- Vinyl Chloride Copolymer (13% vinylacetate), manufactured by Union Carbide C0.

Vinylite VAGH Vinyl Acetate- Vinyl Chloride Copolymer (3% vinylacetate), manufactured by Union Carbide Co.

Ester Gum 8-L Glycerol Ester of Rosin, manufactured by Hercules PowderCo.

Dow 276 V-2 poly-alpha-rnethyl styrene, manufactured by Dow Chemical Co.

1 WVTR determined by TAPPI Method T 464 M-45, reported in units of gramsper 100 square inches per 24 hours at 95% relative humidity, 98 F.Figures reported throughout are for flat" sheets unless specified asbeing for creased sheets.

2 Indicated heat-seal readings are determined as follows: Outstanding:Yields fiber tear seals on paper over a wide range of temperaturesincluding l70350 F. Seals with short dwell times'and low contactpressures (thus assuring good performance on high speed equipment). Hasthe ability to bear 15 gram/inch load at sealing temperatures. Requires1 pound/ream or less coating to obtain a fiber tear seal to uncoatedglassine 0. 40 Fair to good.

0. 05 Excellent.

0. 28 Fair to good.

0. l3 [Exceptional gloss] paper.

Excellent: Has the same qualities as Outstanding except that the abilityto bear a load at sealing temperatures is reduced to 5-14 grams] thetrade designation Elvax 420 and Elvax 460; and polyvinyl acetate,manufactured by Union Carbide Co., under the trade designation AYAF,plus low molecular weight polyethylene, such as manufactured by AlliedChemical Corp., under the trade designation AC-6.

In order to establish optimum ratios of wax to the cyclicized rubber andheat-seal modifier constituents, a

. series of tests was made utilizing 100 parts of ROI 92-154,

63.6 parts of Elvax 250, and zero to 327 parts of Sun 4312 Parafiin Wax.The various compositions were applied to both surfaces of a 30-poundplassine substrate, at coat weights ranging from 2.4 pounds per side perream to 3.2 pounds per side per ream. Heat-seal characteristics and WVTRproperties were determined in each instance and are indicated above inTable II.

From the foregoing table, it can be observed that heatsealing propertiesvary as an inverse function of the proportion of parafiin wax employed,while the WVTR properties vary on a direct relationship with the amountof wax. Highly satisfactory results are realized when the amounts ofparaffin wax are in the range of 36 percent of the rubber to about 73percent of the rubber, since all of the coated substrates in this rangehad heat-seal properties characterized as Excellent and WVTR values ofless than .10. Moreover, depending upon the specific end use,compositions including lesser or greater amounts of Wax might besuitable.

A glassine substrate coated on both sides according to item number 6 ofTable II exhibited highly superior gas barrier properties. By way ofexample, the coated glassine has an oxygen transmission rate of about0.03 (cc./ sq. in./mil./24 hrs./1 atm., at 75 F., 0% humidity) ascompared to the transmission rate of polyvinylidene chloride coatedcellophane (at 35% relative humidity), which ranges from 0.5 to 1.5.

Where especially good heat-seal characteristics are desired, and WVTR isless important, wax can be reduced, proportionately, and a compositionconsisting of, say, 100 parts RCI 92-154, 63.6 parts Elvax 250, and 18.2parts wax, applied to a typical fibrous substrate (e.g. glassine), willprovide a fiber tear seal with very low coat weights.

Utilizing a constant, intermediate amount of paraffin wax, a series oftests was run in which the cyclicized rubber-to-heat seal modifier ratiowas varied. This series addition to the foregoing, fiber tear goals wereb i of tests is reflected in Table III below. with coat weights as lowas .6 pound per side per ream.

TABLE III RCI Elvax 250 Sun 4312 Coating 92-154 ercent) paraffinHeat-seal 2 WVTR 1 weight (percent) wax (percent) For footnotes 1 and 2see Table I.

The results indicated in Table III reflect that acceptable Thecomposition of the invention, when applied to a heat-seal properties arerealized over a wide range of suitable packaging material substrate,such as glassine, ratios of RCI 92-154-to-Elvax, holding the wax contentprovides a packaging material with outstanding WVTR constant at aboutpercent. and heat-seal properties in addition to other characteristicsAt the lower levels of RC1 92-154, it was possible to which make thematerial highly desirable for food packrestore the WVTR properties todesirably low values by aging and other applications. While providingfiber tear significantly increasing the amounts of wax. This was done hat Seals, the new composition enable WVTR ratings of at some sacrificeto the heat-seal properties, although even 25 0.01 flat, 0.12 creased tobe achieved. And in this respect, at as high as about 65 percent waxcontent an adequate it should be noted that WVTR flat ratings ten timesas heat-seal was obtained, which was much better than would high as thelast-mentioned value still would be considered be obtained With, for exp Plain WaX 0f WaX modlfied exceptionally good from a commercialstandpoint. By only wrth a vinyl acetatehyl p y' way of furthercontrast, available polymer coated cello- A particularly advantageousformulation for general apo phane fil used fig quently in packaging,have WVTR pllcatlon appe o be Parts RC1 92454: Parts ratings as high as0.7 or about 70 times as high as that 512 17 1 g s j fi 'fti g i ggg szi %g z obtainable with the optimum WVTR formulations accord- Pq HQ, an P11 ing to the invention. Moreover, with the composition of coatrng wasapplied 1n we1ghts of approximately]; 2.7 to 360 the invention WVTRratings we b 610W the 0 1 Pounds Per slde per ream to a vanety of Snstrates y tionally good) rating are readily obtainable (along withsol-vent coating techniques. Determinations were then made for adhesionof the coating composition to the substrate, fiber tear heat seals)under Productlon HdItIOHS using WVTR, heat-seal characteristics, andclarity. The results less than P P Side P Team 1 -pound glassine. arereported in T b1 IV Of particular slgnrficance as regards the commercialBy way of further example, but not of limitation, other 40 use of thenew Coating Composition for food Packaging satisfactory substrates arefilms of styrene, nylon, Saran, applications and the like is the factthat the composition, and tetrafluoroethylene. in addition to providingparticularly good WVTR and TABLE IV Substrate Adhesion WVTR Heat-seal 2Clarity Glassine Very good 0.02 Excellent Bleached kraft paper high o-do0. 19 do quality. Bleached kraft paper low do For footnotes 1 and 2 seeTable I.

In order to establish the overall heat-seal characteristics heat-sealcharacteristics, provides very good clarity and of a typical formulationof the composition of the invenis free of undesirable odors andresistant to blocking; tion, various weights of a given formulation wereapplied It Will be understood that the exact formulations mento ableached kraft substrate. The formula in question was tioned herein arerepresentative only, and reference should 100 parts RCI 92-154, 63 partsElvax 3602, and 54.5 be made to the following appended claims indetermining parts Sun 4312 Paraflin Wax. At a typical coat weight thefull scope of the invention.

of 3 pounds per side per ream, fiber tear seals were made We claim:

at heat-seal temperatures ranging from 160 F. to over 65 1. A flexiblepackaging material having properties of 375 F. With temperatures inexcess of 200 F., the minhigh resistance to water vapor transmission,heat sealimum dwell time was less than /2 second, and tentative ability,hot tack and jaw release, comprising:

seals were obtained using contact pressure down to as (a) a substratecoated with a coating composition low as 6 p.s.i. (the lower limit ofthe test equipment). adapted to contribute said properties;

Hot tack was particularly good; a bleached kraft substrate (b) aidcomposition including a i i l fil coated 3 pounds per side per rea-msealed coating-to-coatforming constituent, a highly saturated cyclicizeding was able to support 25 grams per inch at 225 F. In rubber having aniodine number not in substantial excess of and having a melting point ofat least 1 Elvax 3602 (designation of January 10, 1964) is availableapproximately C as of the filing (late of this application as Elvax 40,from Du Pout (c) said highly saturated cyclicized rubber being presentin amounts ranging from approximately 25- 70% by weight of saidcomposition;

((1) the balance of said coating composition including high meltingpoint parafiin wax and a heat scalable material selected from the groupconsisting of polyvinyl acetate, polyvinyl butyral, copolymers of vinylacetate-and ethylene having approximately 18-40% vinyl acetate,copolymers of vinyl acetate and vinyl chloride having approximately3-13% vinyl acetate, glycerol esters of rosin, polystyrene, polyisobutylmethacrylate, and low molecular weight polyethylene;

(e) said high melting point paraffin wax being present in amountsranging from approximately 18-65% by weight of said composition; and

(f) said heat scalable material being present in amounts fromapproximately 3-65% by weight of said composition.

2. A packaging material in accordance with claim 1,

in which said cyclicized rubber is further characterized as having thefollowing properties:

Specific gravity-25 C 1.00 Wt. per gal-25 C. 8.33 Bulking value-25 C.0.120 Index of refraction-25 C 1.535 Color, U.S.D.A., Rosin scale MMelting point, B & R method, C 145-165 Melting point, capillary method,C 125-135 Molecular weight, average 5,000-10,000 Iodine value 75-95 Acidvalue 0-1 Saponification value 0 Burning rate Very slow Dielectricconstant, 1000 cy. 1.35-1.50 Specific surface resistance, ohm. 10Hardness, Sward 50-60 3. A flexible packaging material in accordancewith claim 1, in which (a) said heat scalable material is a copolymer ofvinyl 10 acetate and ethylene having approximately 18-40% vinyl acetate.

4. A packaging material in accordance with claim 3,

in which (a) said cyclicized rubber is present in greater amounts thaneither of said wax and said copolymer; and

(b) said substrate is selected from the group consisting of glassine,bleached kraft paper, cellophane film, polyester film, polyethylenefilm, polypropylene film, aluminum foil, cellulose acetate film,polycarbonate film, styrene film, nylon film, Saran film, andtetrafiuor-oethylene film.

5. A packaging material in accordance with claim 3,

in which (a) said cyclicized rubber is present in amounts greater than40 percent by weight of said composition and less than 60 percent.

6. A packaging material in accordance with claim 3,

in which (a) said cyclicized rubber comprises approximately percent byweight of said composition;

(b) said high melting point parafiin wax comprises approximately 20percent by weight of said composition; and

(c) said copolymer of vinyl acetate and ethylene comprises approximately30 percent by weight of said composition.

References Cited UNITED STATES PATENTS 2,376,778 5/1945 Kallander260-734 2,413,432 12/ 1946 Carson 260-734 2,661,340 12/1953 Van Veersen260-768 3,020,170 2/1962 Macauley 260-734 3,025,167 3/1962 Butler260-285 3,189,573 6/1965 Oken 260-285 MURRAY TILLMAN, Primary Examiner.

M. TULLY, Assistant Examiner.

